The mechanism of carotenoid degradation and the changes in the activities of related enzymes in flue-cured tobacco at the leaf-drying stage during the bulk-curing process were studied in order to provide theoretical b...The mechanism of carotenoid degradation and the changes in the activities of related enzymes in flue-cured tobacco at the leaf-drying stage during the bulk-curing process were studied in order to provide theoretical basis for optimization of curing technology. The effect of different rising speeds of temperature on the carotenoid degradation and the related enzymes activities at the color-fixing stage during the bulk curing process was studied by using the electric-heated flue-curing barn designed by Henan Agricultural University, China, based on curing technology with yellowing at low temperature and moderate humidity and leaf drying at moderate humidity. The results showed that the carotenoid degradation components (β-carotene, lutein, neoxanthin, and violaxthin) decreased gradually at the color-fixing stage during the bulk curing process. The carotenoid degradation components viz., β-carotene, lutein, neoxanthin, and violaxthin at the slow heating curing (T1) were relatively higher than the rapid heating curing (T2) accounting for 10, 2, 32 and 32% respectively, but there were no differences among treatments (P > 0.05). The effect of different conditions of curing on the activities of enzymes related to carotenoids degradation were significant. The lipoxygenase, phenylalanine ammonialyase, peroxidase, and polyphenol oxidase enzymes had a bidirectional effect on the quality of tobacco leaves and it was beneficial to form more premise matter of aroma based on the higher enzyme activities at the early leaf-drying stage. The slow heating could regulate the change in various enzymes’ activities reasonably, making cell redox reaction to reach the dynamic balance and make the degradation of carotenoids adequately. Meanwhile, it could avoid the occurrence of browning reaction and provide foundation for improving the quality of tobacco and optimization of technology for bulk curing and further enhancing aroma.展开更多
In order to find out the correlation between tobacco quality evaluation indicators in China's traditional " moderate aroma" tobaccoproducing areas and simplify the tobacco quality evaluation indicators,w...In order to find out the correlation between tobacco quality evaluation indicators in China's traditional " moderate aroma" tobaccoproducing areas and simplify the tobacco quality evaluation indicators,we evaluate the appearance quality and smoking quality of 143 flue-cured tobacco leaf samples in China's " moderate aroma" tobacco-producing areas,test the physical traits and chemical component,and analyze the canonical correlation between four quality evaluation indicators. The results show that there is significant or extremely significant canonical correlation between four evaluation indicators( tobacco smoking quality,chemical component,appearance quality and physical trait quality); the cumulative variance contribution rate of evaluation indicators is in the order of chemical component( 69. 17%) > appearance quality( 68. 76%) > physical traits( 64. 13%); appearance quality is most closely related to physical traits( 93. 84%). The individual indicators for tobacco quality evaluation make different contribution to the correlation between quality evaluation indicators. The chemical component evaluation indicators mainly include total sugar and ratio of total sugar to betaine; sensory taste indicators mainly include aroma volume,smoke concentration,irritation and softness degree; physical trait evaluation indicators mainly include leaf weight,leaf length and leaf density; appearance quality indicators mainly include leaf organizational structure,color,maturity and identity. Studies have shown that in the large-scale ecoregion,using canonical correlation analysis to simplify tobacco quality evaluation indicators is feasible.展开更多
The changes in the activity of amylase and amylase-isoenzyme and the degradation of starch and pigment of tobacco leaf during flue-curing were studied by using the electric- heated flue-curing barn designed and made b...The changes in the activity of amylase and amylase-isoenzyme and the degradation of starch and pigment of tobacco leaf during flue-curing were studied by using the electric- heated flue-curing barn designed and made by the Henan Agricultural University. The temperature and humidity of the barn were controlled automatically. The results indicated that starch in tobacco leaf decreased rapidly and leveled off after 48 h of curring, in the meantime, the content of soluble sugar increased accordingly and reached a peak at the stage of color-fixing. Both of them had a rapid-changing stage in the first 36 hours of yellowing. The changes of starch and soluble sugar contents had highly significant negative-correlation at 1 % level (rNC89 = -0.8962**, rYY85 = -0.9704**). The activity of amylase increased with the proceeding of curing and reached a peak after 36 hours of curing, then decreased. But the activity of amylase kept at a high level when the humidity of curing-environment was very low, even if the tobacco leaf had been dried. The rapid degradation of starch showed a significantly negative correlation with the increase of activity of amylase at 5 % level (rNC89 = -0.8495*, rYY85 = -0.7839*). The degradation of starch and pigment had the same regulation and had highly significant correlation at 1 % level (rNC89= 0.9649**, rYY85= 0.9428**). There were mainly three amylase-isoenzyme bands -A, B, C respectively, in tobacco leaf during flue curing. They were identified as α-AMY, β-AMY, R-AMY, and the activity of β-AMY was the highest. The changes in amylase activity and contents of starch and pigment were affected by the tobacco leaf moisture and environmental humidity during curing.展开更多
Nitrogen(N)supply is the most important factor affecting yield and quality of flue-cured tobacco(FCT).A field experiment and an in situ incubation method were used to study the effects of soil N mineralization in the ...Nitrogen(N)supply is the most important factor affecting yield and quality of flue-cured tobacco(FCT).A field experiment and an in situ incubation method were used to study the effects of soil N mineralization in the later stages of growth on yield and nicotine content of FCT in Fenggang and Jinsha,Guizhou Province.The yield and market value of FCT at Fenggang were much lower than those at Jinsha.However,the nicotine content of middle and upper leaves was much higher at Fenggang than at Jinsha when the same rate of fertilizer N was applied,which might be due to a higher N supply capacity at the Fenggang site.At later stages of growth(7-16 weeks after transplanting),the soil net N mineralization at Fenggang(56 kg N ha^(-1))was almost double that at Jinsha(30 kg N ha^(-1)).While soil NH_4-N and NO_3-N were almost exhausted by the plants or leached 5 weeks after transplanting,the N taken up at the later growth stages at Fenggang were mainly derived from soil N mineralization,which contributed to a high nicotine content in the upper leaves.The order of soil N contribution to N buildup in different leaves was:upper leaves>middle leaves>lower leaves.Thus,soil N mineralization at late growth stages was an important factor affecting N accumulation and therefore the nicotine content in the upper leaves.展开更多
The importance of controlled temperature during the four-days co-cultivation period was evaluated under the most physiologically relevant conditions for Agrobacterium tumefaciens-mediated transformation of tobacco (Ni...The importance of controlled temperature during the four-days co-cultivation period was evaluated under the most physiologically relevant conditions for Agrobacterium tumefaciens-mediated transformation of tobacco (Nicotiana tabacum L. cv. Xanthi (nn, Smith)) leaf disks. We compared the effect of temperatures ranging from 15°C, 18°C, 20°C, 22°C to 25°C on the stable expression of β-glucuronidase (GUS) activity of 14 days old hygromycin-selected leaf disks, and on the increase in the fresh weight yield of 28 days old kanamycin-selected calli. The highest average of GUS activity was obtained at 20°C among the five temperatures tested although the difference between the 18°C and 20°C treatment was not statistically significant. The GUS activity at 15°C was statistically lower than those at 18°C and 20°C. The GUS activity in 22°C treatment was an intermediate between the highest (18/20°C) and second highest averages (15°C), and was not statistically significantly different. The lowest average of GUS activity was observed at 25°C. The highest increase in the plate average of fresh weight yield was obtained at 20°C among the five temperature tested. The 20°C treatment was statistically significantly better than the 15°C and 18°C treatments. The 20°C co-cultivation treatment resulted in the higher FW yield than 22°C and 25°C even though the differences were not statistically significant. In conclusion, low co-cultivation temperature at 20°C resulted in the reproducible maximum increase in both the fresh weight yield and stable expression of GUS activity after transformation of tobacco leaf disks.展开更多
Complicated changes are happening during the aging process of flue-cured tobacco (FCT) and understanding of the changing components is of great significance in improving the quality,shortening aging time,and enhancing...Complicated changes are happening during the aging process of flue-cured tobacco (FCT) and understanding of the changing components is of great significance in improving the quality,shortening aging time,and enhancing production and economic efficiency in tobacco industry.The aging samples of FCT from four main producing areas of China,i.e.,Yunnan,Sichuan,Hubei,and Dongbei,were used to study the changing rule of the components such as alkali,acid,and carbohydrate as well as the aroma and their relationship with sensory quality;and based on the correlation among the components and the sensory quality index,multivariable models were established to predict the aging quality.The results showed that the sensory quality of FCT increased steadily during the aging time,and at the same time,the acidic components (total organic acids,volatile acids) increased gradually,while the alkaline substances (nicotine,volatile alkali),carbohydrate (total sugars,reducing sugar) and pH values showed a downward trend.Correlation analysis found that the sensory quality and pH values were negatively correlated (P<0.05),while the sensory quality with total organic acids and aroma were positively correlated.The optimal model for predicting the quality of FCT was y=56.75-0.63x12+50.09x2-13.27x22,(y:sensory quality;x1:pH;x2:total organic acids).The average predicating error was 1.04% with maximum predicating error of 2.89% and the accuracy rate of above 97%.展开更多
Effect of environmental humidity and water content in tobacco leaf on starch metabolism was studied by using the electric-heated auto-controlled flue-curing barn supplied by Henan Agricultural University, China. The r...Effect of environmental humidity and water content in tobacco leaf on starch metabolism was studied by using the electric-heated auto-controlled flue-curing barn supplied by Henan Agricultural University, China. The results indicated that the degradation of starch and decrease of water content in tobacco leaf during early yellowing at low humidity was the most rapid, and the water loss was the highest while the lowest under high humidity. The duration for starch degradation under low humidity was longer than that of CK. So the starch residue in cured leaf of different treatment took the order of high humidity yellowing treatment＞low humidity yellowing treatment＞ CK. When the leaf water content was decreased to around 50%, the starch degradation became slow and the content of starch was stable. Starch degradation and decrease of leaf water content was not synchronous. Starch in tobacco leaf during yellowing degraded more rapidly when humidity was decreased at a high speed, but the degradation stopped earlier at late stage. There was a quicker and higher degradation of starch under high environmental humidity. When the humidity decreased to 70 %,the content of starch was stable. The activity of amylase began to decrease when relative humidity was below 75 %, but it kept a high level of activity when the environmental humidity was below 70 %.展开更多
The experiment was set up for examining the physiological and biological indexes quickly and exactly, for obtaining information of tobacco-field fertilizing and tobacco growing. The ASD Field spec FR 2500 was used to ...The experiment was set up for examining the physiological and biological indexes quickly and exactly, for obtaining information of tobacco-field fertilizing and tobacco growing. The ASD Field spec FR 2500 was used to measure spectra reflectance of flue-cured tobacco and the relationship between hyperspectral parameters and biochemical contents (total nitrogen, chlorophyll, carotenoid), and physiological indexes (fresh weight, dry weight, moisture content) of flue-cured tobacco leaves was studied by correlation and stepwise regression statistic methods at different nitrogen and potassium levels. The results indicated that the spectra curves of different treatments had obvious rules and great diversities. There were high correlations between different types of spectra parameters and ten physiological and biochemical indexes of flue-cured tobacco leaves. Hyperspectral characteristic variables of ten physiological and biochemical indexes were found through stepwise regression, and SDr/SDb was the characteristic variable closest to seven biochemical contents. Simultaneously, the R2 and regression coefficient of equations reached 0.05 significant level and the equations had good estimating effects through the examination of other samples. Accordingly, this study suggested that the ten physiological and biochemical indexes could be estimated quickly by the estimating models, at the same time nitrogen-potassium fertilization and growth condition of flue-cured tobacco could be inspected.展开更多
Nicotine is a secondary substance synthesized in tobacco roots. In flue-cured tobacco planting,tobacco decapitation is an effective practice to promote nicotine biosynthesis by regulation of the redistribution of tota...Nicotine is a secondary substance synthesized in tobacco roots. In flue-cured tobacco planting,tobacco decapitation is an effective practice to promote nicotine biosynthesis by regulation of the redistribution of total nitrogen amounts. However,proteins relevant to nicotine synthesis in tobacco roots has not been identified and characterized yet. It is important to explore the regulation of nicotine biosynthesis in tobacco roots. To identify the proteins relevant to nicotine synthesis,the protein patterns in roots of flue-cured tobacco (cv. K326) before and after decapitation were analyzed. In the present study,the protein patterns in roots of flue-cured tobacco were analyzed by two-dimensional electrophoresis (2-DE),and the differentially-expressed spots were identified by matrix assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF-MS). Paired comparison of 2-DE maps revealed 26 spots of differentially-expressed proteins in roots before and after decapitation. Furthermore,nine differentially-expressed spots were identified. There were four proteins which were enzymes possibly involved in nicotine biosynthesis. In addition,the roles of the four enzymes in nicotine biosynthesis were discussed in a putative network. Our results would contribute to the understanding of the regulation pathway of nicotine biosynthesis and further to the molecular manipulation on the nicotine contents in flue-cured tobacco.展开更多
The effect of different ratio of organic and inorganic fertilizers on the growth and the yield and quality of flue-cured tobacco was studied.Using randomized blocks design,the data of the test materials K326 were anal...The effect of different ratio of organic and inorganic fertilizers on the growth and the yield and quality of flue-cured tobacco was studied.Using randomized blocks design,the data of the test materials K326 were analyzed by using variance analysis,significance test and other methods.The release efficiency of organic fertilizer in the soil was slower,and the effect of organic fertilizer on the growth of tobacco plants was worse than that of chemical fertilizers,and under 25% organic fertilizer + 75% chemical fertilizer treatment,the quality of the fluecured tobacco was good.Under the treatment of 50% organic fertilizer + 50% chemical fertilizer,the production of flue-cured tobacco was high and the ratio of first-class tobacco was high.It is suggested that the organic fertilizer application ratio should be 25%-50% in the agricultural production.展开更多
Solving high-temperature plastic mulching film-induced leaf burning in the first week during tobacco cultivation would take much time and effort. In the present study, the growth as well as the leaf sugar and nicotine...Solving high-temperature plastic mulching film-induced leaf burning in the first week during tobacco cultivation would take much time and effort. In the present study, the growth as well as the leaf sugar and nicotine contents of seedlings with or without leaf burning induced by high-temperature plastic mulching film were tested at two independent sites in 2015 and 2016 to identify the influence of leaf burning on seedling growth. The results showed that the growth of seedlings with leaf burning was improved with increased leaf area, leaf number and plant height compared to those without leaf burning, combined with an increased seedling survival rate at two sites in two years. In seedlings with leaf burning, the contents of fructose and glucose increased and peaked at 11:00 and 13:00 in the leaf and root, respectively, with an increased root nicotine content beginning at 13:00, highlighting the signalling role of sugars. Activities of antioxidant enzymes including peroxidase(POD), superoxide dismutase(SOD) and catalase(CAT) were all increased in seedlings with leaf burning. More plant biomass was allocated to roots in seedlings with leaf burning with increased root volume compared to control seedlings, which might facilitate the absorption of water and nutrients from the soil. Our findings demonstrate that high-temperature plastic mulching film-induced leaf burning not inhibited but benefited seedling survival and growth, suggesting that the time and labour-consuming manual plucking of burnt leaves can be avoided during tobacco cultivation.展开更多
This study was to investigate the main traits of potassium-enriched, flue-cured tobacco genotypes related to potassium absorption, accumulation, and in-ward potassium currents of the root cortex. Hydroponic methods, K...This study was to investigate the main traits of potassium-enriched, flue-cured tobacco genotypes related to potassium absorption, accumulation, and in-ward potassium currents of the root cortex. Hydroponic methods, K+-depletion methods, and patch-clamp, whole-cell recordings were conducted to study the accumulation of dry matter and potassium in different organs, and to measure potassium absorption and dynamic and in-ward potassium currents in potassium-enriched, flue- cured tobacco genotypes. The average dry weights of leaves and whole plant of potassium-enriched, flue-cured tobacco genotype ND202 were 10.20, and 14.85 g, respectively, higher than JYH (8.50 and 13.11 g, respectively) and NC2326 (8.39 and 12.72 g, respectively), when potassium concentration in the solution ranged from 0.1 to 50 mmol L-1. Potassium accumulation in the leaves of ND202 was 18.6% higher than JYH and 34% higher than NC2326 when potassium concentration in the solution was superior to 0.5 mmol L-1. The Vmax (the maximum velocity) of ND202 was 118.11 μmol FW g-1 h-1, obviously higher than that of JYH (58.87 μmol FW g-1 h-1) and NC2326 (64.40 μmol FW g-1 h-1). In the in-ward potassium currents, the absolute value of current density (pA/pF) of ND202 was 60, higher than that of JYH (50) and NC2326 (40). Potassium concentration in leaves, Vmax, and in-ward potassium currents, could be used to screen potassium-enriched, flue-cured tobacco genotypes.展开更多
[Objective] The aim was to construct the internal motivation of flued-cured tobacco natural aging. [Method] The variation of DNA copies of Bacillus megaterium, amylase activity, PPO, peroxydase and content of starch, ...[Objective] The aim was to construct the internal motivation of flued-cured tobacco natural aging. [Method] The variation of DNA copies of Bacillus megaterium, amylase activity, PPO, peroxydase and content of starch, neutro-protein, polyphenol in different aging period were investigated using Henan flue-cured tobacco leaves. [Result] Results showed that the DNA copies of Bacillus megaterium increased initially but decreased subsequently with the aging time. The DNA copies of Bacillus per gram of tobacco leaf surface reached the maximum number at 6 months aging. The activities of four enzymes showed the same variation trend as in DNA copies, and also reached the highest level at 6 months aging. Chemical ingredients, however, displayed a downward trend. The variation of enzyme activity and content of chemical composition were reflected in the changes of DNA copies in Bacillus megaterium. [Conclusion] The result indicate that Bacillus megaterium was the internal motivation of flue-cured tobacco natural aging.展开更多
The growth, chlorophyll composition, photosynthesis, respiration, K uptake and root K+ secretion offlue-cured tobacco as thected by different concentrations of N supplied as urea, NaNO3 and NH4NO3 werestudied under th...The growth, chlorophyll composition, photosynthesis, respiration, K uptake and root K+ secretion offlue-cured tobacco as thected by different concentrations of N supplied as urea, NaNO3 and NH4NO3 werestudied under the experimental condition of sand culture. The results showed that the content of K in thefiue-cured tobacco was not merely related with root vitality and uptake but also closely related with root cellmembrane structure and K+ secretion.展开更多
[Objective]This study aimed to compare the effects of low-temperature low-humidity tobacco flue-curing technology,moderate-temperature moderatehumidity tobacco flue-curing technology and moderate-temperature high-humi...[Objective]This study aimed to compare the effects of low-temperature low-humidity tobacco flue-curing technology,moderate-temperature moderatehumidity tobacco flue-curing technology and moderate-temperature high-humidity tobacco flue-curing technology on submicroscopic structure of flue-cured tobacco leaves to provide theoretical basis for tobacco flue-curing. [Method] Middle leaves of tobacco cultivar K326 were collected in Pengshui County of Chongqing City for flue-curing experiment using three flue-curing technologies. Leaf samples were collected regularly in the flue-curing process,to investigate the submicroscopic structure of flue-cured tobacco leaves. [Result]Morphology changes and structural rupture of chloroplasts occurred at different time during three flue-curing processes. In low-temperature low-humidity flue-curing process,morphology changes and structural rupture of chloroplasts occurred late but rapidly; in moderate-temperature moderate-humidity flue-curing process and moderate-temperature high-humidity flue-curing process,morphology changes and structural rupture of chloroplasts occurred early but slowly. Among these three flue-curing processes,the speed of changes in mitochondria morphology,cristae number and membrane rupture presented an upward order of low-temperature low-humidity flue-curing process < moderate-temperature high-humidity flue-curing process < moderate-temperature moderate-humidity flue-curing process. In low-temperature low-humidity flue-curing process,starch granules in chloroplasts ruptured after flue-curing for 36- 48 h;in moderate-temperature moderate-humidity flue-curing process,starch granules in chloroplasts ruptured after flue-curing for 24- 36 h; in moderate-temperature high-humidity flue-curing process,starch granules in chloroplasts ruptured after flue-curing for 12- 24 h. [Conclusion]Using low-temperature low-humidity fluecuring technology could prolong the maintenance duration of the submicroscopic structure integrity of flue-cured tobacco leaves,which was conducive to fully decomposing and transforming substances in tobacco leaves and obtaining high-quality flue-cured tobacco leaves.展开更多
[Objective]This study aimed to compare the effects of Chinese quality-improving fragrance-increasing tobacco flue-curing technology,Chinese threestage tobacco flue-curing technology and Zimbabwean tobacco flue-curing ...[Objective]This study aimed to compare the effects of Chinese quality-improving fragrance-increasing tobacco flue-curing technology,Chinese threestage tobacco flue-curing technology and Zimbabwean tobacco flue-curing technology on microscopic structure of flue-cured tobacco leaves to provide theoretical basis for tobacco flue-curing. [Method]Middle leaves of tobacco cultivar K326 were collected in Pengshui County of Chongqing City for flue-curing experiment using three flue-curing technologies. Leaf samples were collected regularly in the flue-curing process,to investigate the microscopic structure of flue-cured tobacco leaves.[Result]During three flue-curing processes,leaves,palisade tissues and sponge tissues shrank gradually. Three flue-curing processes exhibited significant differences in the peak of tissue shrinkage: microscopic structure of flue-cured tobacco leaves in Chinese three-stage tobacco flue-curing process shrank earliest,follower by Chinese quality-improving fragrance-increasing tobacco flue-curing process; flue-cured tobacco leaves in Zimbabwean tobacco flue-curing process presented the latest shrinkage. At 84 h post-curing,leaf thickness in three flue-curing processes showed a descend order of Chinese three-stage tobacco flue-curing process >Chinese quality-improving fragrance-increasing tobacco flue-curing process > Zimbabwean tobacco flue-curing process. Upper and lower epidermal cells in Zimbabwean tobacco flue-curing process ruptured earlier than other two flue-curing processes; eventually,the majority of cells ruptured and mixed with palisade tissues and sponge tissues. In Chinese quality-improving fragrance-increasing tobacco flue-curing process,only a small number of epidermal cells in dried leaves ruptured.Among three flue-curing technologies,Zimbabwean tobacco flue-curing technology exhibited the greatest damage to epidermal cells,followed by Chinese three-stage tobacco flue-curing technology; Chinese quality-improving fragrance-increasing tobacco flue-curing technology had the minimum damage to epidermal cells. Mesophyll cross-section exhibited significant morphological changes in stomata. To be specific,at 0- 12 h post-curing,stomata of tobacco leaves closed with slightly prominent stomatal apparatuses on upper and lower epidermis; at 24- 72 h post-curing,stomata of tobacco leaves changed gradually from opening to closure with significantly prominent stomatal apparatuses on upper and lower epidermis; at 84 h post-curing,stomata of tobacco leaves closed,and the majority of stomatal apparatuses were significantly prominent. In Chinese quality-improving fragrance-increasing tobacco flue-curing process,only a small number of epidermal cells ruptured at 84 h post-flue-curing; palisade tissues and sponge tissues shrank almost simultaneously. Significant gaps were observed between palisade tissues and between palisade tissues and sponge tissues. Chinese quality-improving fragrance-increasing tobacco flue-curing technology exhibited lower disorder level compared with other two flue-curing technologies. [Conclusion]Chinese quality-improving fragrance-increasing tobacco flue-curing technology was conducive to maintaining the microscopic structure integrity of flue-cured tobacco leaves and obtaining high-quality flue-cured tobacco leaves.展开更多
Heavy metals not only adversely affect the quality of tobacco leaves,but also have very adverse effects on human health. In order to find out the effective cultivation method of controlling heavy metal content in flue...Heavy metals not only adversely affect the quality of tobacco leaves,but also have very adverse effects on human health. In order to find out the effective cultivation method of controlling heavy metal content in flue-cured tobacco,the content of four kinds of heavy metals in soil and tobacco leaves in different intercropping treatments was tested. The results showed that there were significant differences between the effects of intercropping on the content of some heavy metals in soil and tobacco leaves. Different interplanting methods had a positive effect on the reduction of heavy metal content in tobacco leaves and play a very important and positive role in actual production.展开更多
The risk regionalization of drought for flue-cured tobacco planting in Qujing City was studied to provide reference for drawing on advantages and avoiding disadvantages in flue-cured tobacco planting,disaster reductio...The risk regionalization of drought for flue-cured tobacco planting in Qujing City was studied to provide reference for drawing on advantages and avoiding disadvantages in flue-cured tobacco planting,disaster reduction,and disaster relief services.According to the production practice of flue-cured tobacco and local climate analysis,the risk of disaster-causing factors,sensitivity of disaster-breeding environment,vulnerability of carriers,and disaster prevention and reduction capability were analyzed and evaluated quantitatively.Secondly,starting from the formation mechanism of drought,a risk assessment model of the meteorological disaster was established by GIS technology.Finally,the risk assessment and regionalization of drought in the critical periods for drought-stricken flue-cured tobacco (transplanting period,root extending stage and vigorous growth period) in Qujing City were carried out.The results showed that in Qujing City,the risk areas of drought for flue-cured tobacco planting were divided into five grades in the transplanting period and six grades in the root extending stage and vigorous growth period.展开更多
The effects of amount of green manure returned to field on yield and quality of flue-cured tobacco were studied by field experiment. The results showed that significant positive correlation existed between tobacco lea...The effects of amount of green manure returned to field on yield and quality of flue-cured tobacco were studied by field experiment. The results showed that significant positive correlation existed between tobacco leaf yield and small or moderate amount of green manure returned to field. Path analysis showed that moderate amount of green manure returned to field affected yield and quality of tobacco leaves,small green manure returned to field mainly affected leaf yield,while large amount of green manure returned to field mainly affected leaf quality. Therefore,the effect of moderate amount of green manure returned to field on yield and quality of tobacco leaves was best,and moderate amount of green manure returned to field was recommended in production of flue-cured tobacco.展开更多
This paper aims to explore comprehensive utilization way of discarded fresh tobacco leaf. Based on modern tobacco demands on green,environmental protection and sustainable development,as well as actual situation of bi...This paper aims to explore comprehensive utilization way of discarded fresh tobacco leaf. Based on modern tobacco demands on green,environmental protection and sustainable development,as well as actual situation of biogas production facility in some villages of local tobacco area,this paper selects Longwan Village of Fengshiyan Town as the experimental site and explores the rational way of discarded fresh tobacco leaf biogas fermentation. Results show that cutting and fermentation of discarded fresh tobacco leaf before adding into biogas digester is conductive to improving p H in fermentation process,reducing crust amount,and effectively improving biogas production amount and rate. The study can provide reference for effective processing and rational utilization of discarded fresh tobacco leaf.展开更多
基金supported by the Key Project of State Tobacco Monoply Administration of China(3300806156)
文摘The mechanism of carotenoid degradation and the changes in the activities of related enzymes in flue-cured tobacco at the leaf-drying stage during the bulk-curing process were studied in order to provide theoretical basis for optimization of curing technology. The effect of different rising speeds of temperature on the carotenoid degradation and the related enzymes activities at the color-fixing stage during the bulk curing process was studied by using the electric-heated flue-curing barn designed by Henan Agricultural University, China, based on curing technology with yellowing at low temperature and moderate humidity and leaf drying at moderate humidity. The results showed that the carotenoid degradation components (β-carotene, lutein, neoxanthin, and violaxthin) decreased gradually at the color-fixing stage during the bulk curing process. The carotenoid degradation components viz., β-carotene, lutein, neoxanthin, and violaxthin at the slow heating curing (T1) were relatively higher than the rapid heating curing (T2) accounting for 10, 2, 32 and 32% respectively, but there were no differences among treatments (P > 0.05). The effect of different conditions of curing on the activities of enzymes related to carotenoids degradation were significant. The lipoxygenase, phenylalanine ammonialyase, peroxidase, and polyphenol oxidase enzymes had a bidirectional effect on the quality of tobacco leaves and it was beneficial to form more premise matter of aroma based on the higher enzyme activities at the early leaf-drying stage. The slow heating could regulate the change in various enzymes’ activities reasonably, making cell redox reaction to reach the dynamic balance and make the degradation of carotenoids adequately. Meanwhile, it could avoid the occurrence of browning reaction and provide foundation for improving the quality of tobacco and optimization of technology for bulk curing and further enhancing aroma.
基金Supported by Special Major Research Project of China National Tobacco Corporation(TS-02-20110012)
文摘In order to find out the correlation between tobacco quality evaluation indicators in China's traditional " moderate aroma" tobaccoproducing areas and simplify the tobacco quality evaluation indicators,we evaluate the appearance quality and smoking quality of 143 flue-cured tobacco leaf samples in China's " moderate aroma" tobacco-producing areas,test the physical traits and chemical component,and analyze the canonical correlation between four quality evaluation indicators. The results show that there is significant or extremely significant canonical correlation between four evaluation indicators( tobacco smoking quality,chemical component,appearance quality and physical trait quality); the cumulative variance contribution rate of evaluation indicators is in the order of chemical component( 69. 17%) > appearance quality( 68. 76%) > physical traits( 64. 13%); appearance quality is most closely related to physical traits( 93. 84%). The individual indicators for tobacco quality evaluation make different contribution to the correlation between quality evaluation indicators. The chemical component evaluation indicators mainly include total sugar and ratio of total sugar to betaine; sensory taste indicators mainly include aroma volume,smoke concentration,irritation and softness degree; physical trait evaluation indicators mainly include leaf weight,leaf length and leaf density; appearance quality indicators mainly include leaf organizational structure,color,maturity and identity. Studies have shown that in the large-scale ecoregion,using canonical correlation analysis to simplify tobacco quality evaluation indicators is feasible.
文摘The changes in the activity of amylase and amylase-isoenzyme and the degradation of starch and pigment of tobacco leaf during flue-curing were studied by using the electric- heated flue-curing barn designed and made by the Henan Agricultural University. The temperature and humidity of the barn were controlled automatically. The results indicated that starch in tobacco leaf decreased rapidly and leveled off after 48 h of curring, in the meantime, the content of soluble sugar increased accordingly and reached a peak at the stage of color-fixing. Both of them had a rapid-changing stage in the first 36 hours of yellowing. The changes of starch and soluble sugar contents had highly significant negative-correlation at 1 % level (rNC89 = -0.8962**, rYY85 = -0.9704**). The activity of amylase increased with the proceeding of curing and reached a peak after 36 hours of curing, then decreased. But the activity of amylase kept at a high level when the humidity of curing-environment was very low, even if the tobacco leaf had been dried. The rapid degradation of starch showed a significantly negative correlation with the increase of activity of amylase at 5 % level (rNC89 = -0.8495*, rYY85 = -0.7839*). The degradation of starch and pigment had the same regulation and had highly significant correlation at 1 % level (rNC89= 0.9649**, rYY85= 0.9428**). There were mainly three amylase-isoenzyme bands -A, B, C respectively, in tobacco leaf during flue curing. They were identified as α-AMY, β-AMY, R-AMY, and the activity of β-AMY was the highest. The changes in amylase activity and contents of starch and pigment were affected by the tobacco leaf moisture and environmental humidity during curing.
基金the Program for Changjiang Scholars and Innovation Research Team in University(No.IRT0511)
文摘Nitrogen(N)supply is the most important factor affecting yield and quality of flue-cured tobacco(FCT).A field experiment and an in situ incubation method were used to study the effects of soil N mineralization in the later stages of growth on yield and nicotine content of FCT in Fenggang and Jinsha,Guizhou Province.The yield and market value of FCT at Fenggang were much lower than those at Jinsha.However,the nicotine content of middle and upper leaves was much higher at Fenggang than at Jinsha when the same rate of fertilizer N was applied,which might be due to a higher N supply capacity at the Fenggang site.At later stages of growth(7-16 weeks after transplanting),the soil net N mineralization at Fenggang(56 kg N ha^(-1))was almost double that at Jinsha(30 kg N ha^(-1)).While soil NH_4-N and NO_3-N were almost exhausted by the plants or leached 5 weeks after transplanting,the N taken up at the later growth stages at Fenggang were mainly derived from soil N mineralization,which contributed to a high nicotine content in the upper leaves.The order of soil N contribution to N buildup in different leaves was:upper leaves>middle leaves>lower leaves.Thus,soil N mineralization at late growth stages was an important factor affecting N accumulation and therefore the nicotine content in the upper leaves.
文摘The importance of controlled temperature during the four-days co-cultivation period was evaluated under the most physiologically relevant conditions for Agrobacterium tumefaciens-mediated transformation of tobacco (Nicotiana tabacum L. cv. Xanthi (nn, Smith)) leaf disks. We compared the effect of temperatures ranging from 15°C, 18°C, 20°C, 22°C to 25°C on the stable expression of β-glucuronidase (GUS) activity of 14 days old hygromycin-selected leaf disks, and on the increase in the fresh weight yield of 28 days old kanamycin-selected calli. The highest average of GUS activity was obtained at 20°C among the five temperatures tested although the difference between the 18°C and 20°C treatment was not statistically significant. The GUS activity at 15°C was statistically lower than those at 18°C and 20°C. The GUS activity in 22°C treatment was an intermediate between the highest (18/20°C) and second highest averages (15°C), and was not statistically significantly different. The lowest average of GUS activity was observed at 25°C. The highest increase in the plate average of fresh weight yield was obtained at 20°C among the five temperature tested. The 20°C treatment was statistically significantly better than the 15°C and 18°C treatments. The 20°C co-cultivation treatment resulted in the higher FW yield than 22°C and 25°C even though the differences were not statistically significant. In conclusion, low co-cultivation temperature at 20°C resulted in the reproducible maximum increase in both the fresh weight yield and stable expression of GUS activity after transformation of tobacco leaf disks.
基金supported by the grants of the Application of Nuclear Techniques in Agriculture from Ministry of Agriculture of China (200803034)China Tobacco Company in Hubei (2006YL0229)China Tobacco Company in Yunnan (2009YN010)
文摘Complicated changes are happening during the aging process of flue-cured tobacco (FCT) and understanding of the changing components is of great significance in improving the quality,shortening aging time,and enhancing production and economic efficiency in tobacco industry.The aging samples of FCT from four main producing areas of China,i.e.,Yunnan,Sichuan,Hubei,and Dongbei,were used to study the changing rule of the components such as alkali,acid,and carbohydrate as well as the aroma and their relationship with sensory quality;and based on the correlation among the components and the sensory quality index,multivariable models were established to predict the aging quality.The results showed that the sensory quality of FCT increased steadily during the aging time,and at the same time,the acidic components (total organic acids,volatile acids) increased gradually,while the alkaline substances (nicotine,volatile alkali),carbohydrate (total sugars,reducing sugar) and pH values showed a downward trend.Correlation analysis found that the sensory quality and pH values were negatively correlated (P<0.05),while the sensory quality with total organic acids and aroma were positively correlated.The optimal model for predicting the quality of FCT was y=56.75-0.63x12+50.09x2-13.27x22,(y:sensory quality;x1:pH;x2:total organic acids).The average predicating error was 1.04% with maximum predicating error of 2.89% and the accuracy rate of above 97%.
文摘Effect of environmental humidity and water content in tobacco leaf on starch metabolism was studied by using the electric-heated auto-controlled flue-curing barn supplied by Henan Agricultural University, China. The results indicated that the degradation of starch and decrease of water content in tobacco leaf during early yellowing at low humidity was the most rapid, and the water loss was the highest while the lowest under high humidity. The duration for starch degradation under low humidity was longer than that of CK. So the starch residue in cured leaf of different treatment took the order of high humidity yellowing treatment＞low humidity yellowing treatment＞ CK. When the leaf water content was decreased to around 50%, the starch degradation became slow and the content of starch was stable. Starch degradation and decrease of leaf water content was not synchronous. Starch in tobacco leaf during yellowing degraded more rapidly when humidity was decreased at a high speed, but the degradation stopped earlier at late stage. There was a quicker and higher degradation of starch under high environmental humidity. When the humidity decreased to 70 %,the content of starch was stable. The activity of amylase began to decrease when relative humidity was below 75 %, but it kept a high level of activity when the environmental humidity was below 70 %.
文摘The experiment was set up for examining the physiological and biological indexes quickly and exactly, for obtaining information of tobacco-field fertilizing and tobacco growing. The ASD Field spec FR 2500 was used to measure spectra reflectance of flue-cured tobacco and the relationship between hyperspectral parameters and biochemical contents (total nitrogen, chlorophyll, carotenoid), and physiological indexes (fresh weight, dry weight, moisture content) of flue-cured tobacco leaves was studied by correlation and stepwise regression statistic methods at different nitrogen and potassium levels. The results indicated that the spectra curves of different treatments had obvious rules and great diversities. There were high correlations between different types of spectra parameters and ten physiological and biochemical indexes of flue-cured tobacco leaves. Hyperspectral characteristic variables of ten physiological and biochemical indexes were found through stepwise regression, and SDr/SDb was the characteristic variable closest to seven biochemical contents. Simultaneously, the R2 and regression coefficient of equations reached 0.05 significant level and the equations had good estimating effects through the examination of other samples. Accordingly, this study suggested that the ten physiological and biochemical indexes could be estimated quickly by the estimating models, at the same time nitrogen-potassium fertilization and growth condition of flue-cured tobacco could be inspected.
基金Natural Science Foundation of Henan Province, China (0624050013)Inovation Foundation of Tobacco Profession Cultivation Key Laboratory,China (06 TCIF 006)
文摘Nicotine is a secondary substance synthesized in tobacco roots. In flue-cured tobacco planting,tobacco decapitation is an effective practice to promote nicotine biosynthesis by regulation of the redistribution of total nitrogen amounts. However,proteins relevant to nicotine synthesis in tobacco roots has not been identified and characterized yet. It is important to explore the regulation of nicotine biosynthesis in tobacco roots. To identify the proteins relevant to nicotine synthesis,the protein patterns in roots of flue-cured tobacco (cv. K326) before and after decapitation were analyzed. In the present study,the protein patterns in roots of flue-cured tobacco were analyzed by two-dimensional electrophoresis (2-DE),and the differentially-expressed spots were identified by matrix assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF-MS). Paired comparison of 2-DE maps revealed 26 spots of differentially-expressed proteins in roots before and after decapitation. Furthermore,nine differentially-expressed spots were identified. There were four proteins which were enzymes possibly involved in nicotine biosynthesis. In addition,the roles of the four enzymes in nicotine biosynthesis were discussed in a putative network. Our results would contribute to the understanding of the regulation pathway of nicotine biosynthesis and further to the molecular manipulation on the nicotine contents in flue-cured tobacco.
基金Supported by Yunnan Tobacco Company Project(2015YN19,2014YN25)
文摘The effect of different ratio of organic and inorganic fertilizers on the growth and the yield and quality of flue-cured tobacco was studied.Using randomized blocks design,the data of the test materials K326 were analyzed by using variance analysis,significance test and other methods.The release efficiency of organic fertilizer in the soil was slower,and the effect of organic fertilizer on the growth of tobacco plants was worse than that of chemical fertilizers,and under 25% organic fertilizer + 75% chemical fertilizer treatment,the quality of the fluecured tobacco was good.Under the treatment of 50% organic fertilizer + 50% chemical fertilizer,the production of flue-cured tobacco was high and the ratio of first-class tobacco was high.It is suggested that the organic fertilizer application ratio should be 25%-50% in the agricultural production.
基金supported by the Science and Technology Foundation of Guizhou Province,China (20146015-2,20152099 and 20161097)the Special Fund for Excellent Young Talents of Guizhou Province,China (201534)the Foundation of Guizhou Academy of Tobacco Science,China (GZYKS2018-02)
文摘Solving high-temperature plastic mulching film-induced leaf burning in the first week during tobacco cultivation would take much time and effort. In the present study, the growth as well as the leaf sugar and nicotine contents of seedlings with or without leaf burning induced by high-temperature plastic mulching film were tested at two independent sites in 2015 and 2016 to identify the influence of leaf burning on seedling growth. The results showed that the growth of seedlings with leaf burning was improved with increased leaf area, leaf number and plant height compared to those without leaf burning, combined with an increased seedling survival rate at two sites in two years. In seedlings with leaf burning, the contents of fructose and glucose increased and peaked at 11:00 and 13:00 in the leaf and root, respectively, with an increased root nicotine content beginning at 13:00, highlighting the signalling role of sugars. Activities of antioxidant enzymes including peroxidase(POD), superoxide dismutase(SOD) and catalase(CAT) were all increased in seedlings with leaf burning. More plant biomass was allocated to roots in seedlings with leaf burning with increased root volume compared to control seedlings, which might facilitate the absorption of water and nutrients from the soil. Our findings demonstrate that high-temperature plastic mulching film-induced leaf burning not inhibited but benefited seedling survival and growth, suggesting that the time and labour-consuming manual plucking of burnt leaves can be avoided during tobacco cultivation.
文摘This study was to investigate the main traits of potassium-enriched, flue-cured tobacco genotypes related to potassium absorption, accumulation, and in-ward potassium currents of the root cortex. Hydroponic methods, K+-depletion methods, and patch-clamp, whole-cell recordings were conducted to study the accumulation of dry matter and potassium in different organs, and to measure potassium absorption and dynamic and in-ward potassium currents in potassium-enriched, flue- cured tobacco genotypes. The average dry weights of leaves and whole plant of potassium-enriched, flue-cured tobacco genotype ND202 were 10.20, and 14.85 g, respectively, higher than JYH (8.50 and 13.11 g, respectively) and NC2326 (8.39 and 12.72 g, respectively), when potassium concentration in the solution ranged from 0.1 to 50 mmol L-1. Potassium accumulation in the leaves of ND202 was 18.6% higher than JYH and 34% higher than NC2326 when potassium concentration in the solution was superior to 0.5 mmol L-1. The Vmax (the maximum velocity) of ND202 was 118.11 μmol FW g-1 h-1, obviously higher than that of JYH (58.87 μmol FW g-1 h-1) and NC2326 (64.40 μmol FW g-1 h-1). In the in-ward potassium currents, the absolute value of current density (pA/pF) of ND202 was 60, higher than that of JYH (50) and NC2326 (40). Potassium concentration in leaves, Vmax, and in-ward potassium currents, could be used to screen potassium-enriched, flue-cured tobacco genotypes.
文摘[Objective] The aim was to construct the internal motivation of flued-cured tobacco natural aging. [Method] The variation of DNA copies of Bacillus megaterium, amylase activity, PPO, peroxydase and content of starch, neutro-protein, polyphenol in different aging period were investigated using Henan flue-cured tobacco leaves. [Result] Results showed that the DNA copies of Bacillus megaterium increased initially but decreased subsequently with the aging time. The DNA copies of Bacillus per gram of tobacco leaf surface reached the maximum number at 6 months aging. The activities of four enzymes showed the same variation trend as in DNA copies, and also reached the highest level at 6 months aging. Chemical ingredients, however, displayed a downward trend. The variation of enzyme activity and content of chemical composition were reflected in the changes of DNA copies in Bacillus megaterium. [Conclusion] The result indicate that Bacillus megaterium was the internal motivation of flue-cured tobacco natural aging.
文摘The growth, chlorophyll composition, photosynthesis, respiration, K uptake and root K+ secretion offlue-cured tobacco as thected by different concentrations of N supplied as urea, NaNO3 and NH4NO3 werestudied under the experimental condition of sand culture. The results showed that the content of K in thefiue-cured tobacco was not merely related with root vitality and uptake but also closely related with root cellmembrane structure and K+ secretion.
基金Supported by General Program of Science and Technology Project of China National Tobacco Corporation[ZYB(2012)No.122]Science and Technology Project of Chongqing Branch of China National Tobacco Corporation(NY20110601070010)
文摘[Objective]This study aimed to compare the effects of low-temperature low-humidity tobacco flue-curing technology,moderate-temperature moderatehumidity tobacco flue-curing technology and moderate-temperature high-humidity tobacco flue-curing technology on submicroscopic structure of flue-cured tobacco leaves to provide theoretical basis for tobacco flue-curing. [Method] Middle leaves of tobacco cultivar K326 were collected in Pengshui County of Chongqing City for flue-curing experiment using three flue-curing technologies. Leaf samples were collected regularly in the flue-curing process,to investigate the submicroscopic structure of flue-cured tobacco leaves. [Result]Morphology changes and structural rupture of chloroplasts occurred at different time during three flue-curing processes. In low-temperature low-humidity flue-curing process,morphology changes and structural rupture of chloroplasts occurred late but rapidly; in moderate-temperature moderate-humidity flue-curing process and moderate-temperature high-humidity flue-curing process,morphology changes and structural rupture of chloroplasts occurred early but slowly. Among these three flue-curing processes,the speed of changes in mitochondria morphology,cristae number and membrane rupture presented an upward order of low-temperature low-humidity flue-curing process < moderate-temperature high-humidity flue-curing process < moderate-temperature moderate-humidity flue-curing process. In low-temperature low-humidity flue-curing process,starch granules in chloroplasts ruptured after flue-curing for 36- 48 h;in moderate-temperature moderate-humidity flue-curing process,starch granules in chloroplasts ruptured after flue-curing for 24- 36 h; in moderate-temperature high-humidity flue-curing process,starch granules in chloroplasts ruptured after flue-curing for 12- 24 h. [Conclusion]Using low-temperature low-humidity fluecuring technology could prolong the maintenance duration of the submicroscopic structure integrity of flue-cured tobacco leaves,which was conducive to fully decomposing and transforming substances in tobacco leaves and obtaining high-quality flue-cured tobacco leaves.
基金Supported by General Program of Science and Technology Project of China National Tobacco Corporation[ZYB(2012)No.122]Science and Technology Project of Chongqing Branch of China National Tobacco Corporation(NY20110601070010)
文摘[Objective]This study aimed to compare the effects of Chinese quality-improving fragrance-increasing tobacco flue-curing technology,Chinese threestage tobacco flue-curing technology and Zimbabwean tobacco flue-curing technology on microscopic structure of flue-cured tobacco leaves to provide theoretical basis for tobacco flue-curing. [Method]Middle leaves of tobacco cultivar K326 were collected in Pengshui County of Chongqing City for flue-curing experiment using three flue-curing technologies. Leaf samples were collected regularly in the flue-curing process,to investigate the microscopic structure of flue-cured tobacco leaves.[Result]During three flue-curing processes,leaves,palisade tissues and sponge tissues shrank gradually. Three flue-curing processes exhibited significant differences in the peak of tissue shrinkage: microscopic structure of flue-cured tobacco leaves in Chinese three-stage tobacco flue-curing process shrank earliest,follower by Chinese quality-improving fragrance-increasing tobacco flue-curing process; flue-cured tobacco leaves in Zimbabwean tobacco flue-curing process presented the latest shrinkage. At 84 h post-curing,leaf thickness in three flue-curing processes showed a descend order of Chinese three-stage tobacco flue-curing process >Chinese quality-improving fragrance-increasing tobacco flue-curing process > Zimbabwean tobacco flue-curing process. Upper and lower epidermal cells in Zimbabwean tobacco flue-curing process ruptured earlier than other two flue-curing processes; eventually,the majority of cells ruptured and mixed with palisade tissues and sponge tissues. In Chinese quality-improving fragrance-increasing tobacco flue-curing process,only a small number of epidermal cells in dried leaves ruptured.Among three flue-curing technologies,Zimbabwean tobacco flue-curing technology exhibited the greatest damage to epidermal cells,followed by Chinese three-stage tobacco flue-curing technology; Chinese quality-improving fragrance-increasing tobacco flue-curing technology had the minimum damage to epidermal cells. Mesophyll cross-section exhibited significant morphological changes in stomata. To be specific,at 0- 12 h post-curing,stomata of tobacco leaves closed with slightly prominent stomatal apparatuses on upper and lower epidermis; at 24- 72 h post-curing,stomata of tobacco leaves changed gradually from opening to closure with significantly prominent stomatal apparatuses on upper and lower epidermis; at 84 h post-curing,stomata of tobacco leaves closed,and the majority of stomatal apparatuses were significantly prominent. In Chinese quality-improving fragrance-increasing tobacco flue-curing process,only a small number of epidermal cells ruptured at 84 h post-flue-curing; palisade tissues and sponge tissues shrank almost simultaneously. Significant gaps were observed between palisade tissues and between palisade tissues and sponge tissues. Chinese quality-improving fragrance-increasing tobacco flue-curing technology exhibited lower disorder level compared with other two flue-curing technologies. [Conclusion]Chinese quality-improving fragrance-increasing tobacco flue-curing technology was conducive to maintaining the microscopic structure integrity of flue-cured tobacco leaves and obtaining high-quality flue-cured tobacco leaves.
基金Supported by Science and Technology Project of Hongyun Honghe Tobacco(Group)Co.,Ltd.(HYHH2013YL01)Tea Science Specialty Practice and Training Base Construction Project of College of Agriculture and Forestry,Pu'er University
文摘Heavy metals not only adversely affect the quality of tobacco leaves,but also have very adverse effects on human health. In order to find out the effective cultivation method of controlling heavy metal content in flue-cured tobacco,the content of four kinds of heavy metals in soil and tobacco leaves in different intercropping treatments was tested. The results showed that there were significant differences between the effects of intercropping on the content of some heavy metals in soil and tobacco leaves. Different interplanting methods had a positive effect on the reduction of heavy metal content in tobacco leaves and play a very important and positive role in actual production.
基金Supported by China National Tobacco Corporation(Yunnan Tobacco Science and Technology Program No.[2014]302,program contract number:2014YN22)
文摘The risk regionalization of drought for flue-cured tobacco planting in Qujing City was studied to provide reference for drawing on advantages and avoiding disadvantages in flue-cured tobacco planting,disaster reduction,and disaster relief services.According to the production practice of flue-cured tobacco and local climate analysis,the risk of disaster-causing factors,sensitivity of disaster-breeding environment,vulnerability of carriers,and disaster prevention and reduction capability were analyzed and evaluated quantitatively.Secondly,starting from the formation mechanism of drought,a risk assessment model of the meteorological disaster was established by GIS technology.Finally,the risk assessment and regionalization of drought in the critical periods for drought-stricken flue-cured tobacco (transplanting period,root extending stage and vigorous growth period) in Qujing City were carried out.The results showed that in Qujing City,the risk areas of drought for flue-cured tobacco planting were divided into five grades in the transplanting period and six grades in the root extending stage and vigorous growth period.
基金Supported by Project of Hunan Tobacco Monopoly Bureau
文摘The effects of amount of green manure returned to field on yield and quality of flue-cured tobacco were studied by field experiment. The results showed that significant positive correlation existed between tobacco leaf yield and small or moderate amount of green manure returned to field. Path analysis showed that moderate amount of green manure returned to field affected yield and quality of tobacco leaves,small green manure returned to field mainly affected leaf yield,while large amount of green manure returned to field mainly affected leaf quality. Therefore,the effect of moderate amount of green manure returned to field on yield and quality of tobacco leaves was best,and moderate amount of green manure returned to field was recommended in production of flue-cured tobacco.
文摘This paper aims to explore comprehensive utilization way of discarded fresh tobacco leaf. Based on modern tobacco demands on green,environmental protection and sustainable development,as well as actual situation of biogas production facility in some villages of local tobacco area,this paper selects Longwan Village of Fengshiyan Town as the experimental site and explores the rational way of discarded fresh tobacco leaf biogas fermentation. Results show that cutting and fermentation of discarded fresh tobacco leaf before adding into biogas digester is conductive to improving p H in fermentation process,reducing crust amount,and effectively improving biogas production amount and rate. The study can provide reference for effective processing and rational utilization of discarded fresh tobacco leaf.
